/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.fnexecution.data;



import com.bff.gaia.unified.sdk.coders.Coder;

import com.bff.gaia.unified.sdk.fn.data.CloseableFnDataReceiver;

import com.bff.gaia.unified.sdk.fn.data.FnDataReceiver;

import com.bff.gaia.unified.sdk.fn.data.InboundDataClient;

import com.bff.gaia.unified.sdk.fn.data.LogicalEndpoint;

import com.bff.gaia.unified.sdk.util.WindowedValue;



/**

 * The {@link FnDataService} is able to forward inbound elements to a consumer and is also a

 * consumer of outbound elements. Callers can register themselves as consumers for inbound elements

 * or can get a handle for a consumer for outbound elements.

 */

public interface FnDataService {



  /**

   * Registers a receiver to be notified upon any incoming elements.

   *

   * <p>The provided coder is used to decode inbound elements. The decoded elements are passed to

   * the provided receiver.

   *

   * <p>Any failure during decoding or processing of the element will put the {@link

   * InboundDataClient} into an error state such that {@link InboundDataClient#awaitCompletion()}

   * will throw an exception.

   *

   * <p>The provided receiver is not required to be thread safe.

   */

  <T> InboundDataClient receive(

	  LogicalEndpoint inputLocation,

	  Coder<WindowedValue<T>> coder,

	  FnDataReceiver<WindowedValue<T>> listener);



  /**

   * Creates a receiver to which you can write data values and have them sent over this data plane

   * service.

   *

   * <p>The provided coder is used to encode elements on the outbound stream.

   *

   * <p>Closing the returned receiver signals the end of the stream.

   *

   * <p>The returned receiver is not thread safe.

   */

  <T> CloseableFnDataReceiver<WindowedValue<T>> send(

	  LogicalEndpoint outputLocation, Coder<WindowedValue<T>> coder);

}